Unable to feed Treeview with entities

[Gyorgy Gorog]

Hi there, I have an MS SQL table from which I derive an Entity Framework DbSet. 

Specifying the DbSet as the TreeView's DataSource results in an error.

If I convert this DbSet to a List or IEnumerable, TreeView remains blank.

Converting the DbSet to an array, a series of empty root nodes appear.

Please advise.

Example Data: (TreeView looks the same if restricted to these data):

PIR	SupervisorPIR	Name	Alive
309271		EMBERI ERŐFORRÁSOK MINISZTÉRIUMA	1
308647	309271	EMBERI ERŐFORRÁSOK MINISZTÉRIUMA ASZÓDI JAVÍTÓINTÉZET, ÁLTALÁNOS ISKOLA, SZAKISKOLA ÉS SPECIÁLIS SZAKISKOLA	1
308636	309271	EMBERI ERŐFORRÁSOK MINISZTÉRIUMA BUDAPESTI JAVÍTÓINTÉZETE	1
308692	309271	EMBERI ERŐFORRÁSOK MINISZTÉRIUMA DEBRECENI JAVÍTÓINTÉZETE	1
840110	309271	EMBERI ERŐFORRÁSOK MINISZTÉRIUMA NAGYKANIZSAI JAVÍTÓINTÉZETE	0
308669	309271	EMBERI ERŐFORRÁSOK MINISZTÉRIUMA RÁKOSPALOTAI JAVÍTÓINTÉZETE ÉS KÖZPONTI SPECIÁLIS GYERMEKOTTHONA	1

Code:

               HuLexEntities huLexEntities = new HuLexEntities();

                CBI[] cbis = huLexEntities.CBIs.AsNoTracking().Where( d => d.PIR == "309271" || d.SupervisorPIR == "309271").ToArray();

                treeCbi.SelfRelationRootValue = "";

                treeCbi.DisplayMember = "Name";

                treeCbi.ParentMember = "SupervisorPIR";

                treeCbi.ChildMember = "PIR";

                treeCbi.ValueMember = "Name";

                treeCbi.CheckedMember = "Alive";

                treeCbi.DataSource = cbis;

Result: 

  

[Gyorgy Gorog]

Hi, the same if I detach data from entities and provide an object array. 

private class SimpleCbi

        {

            public string Pir = string.Empty;

            public string ParentPir = string.Empty;

            public string Name = string.Empty;

            public bool IsAlive = false;

        }

List<SimpleCbi> cbis = new List<SimpleCbi>();

.... add data....

treeCbi.SelfRelationRootValue = "";

                treeCbi.DisplayMember = treeCbi.ValueMember = nameof( SimpleCbi.Name );

                treeCbi.ParentMember = nameof( SimpleCbi.ParentPir );

                treeCbi.ChildMember = nameof( SimpleCbi.Pir );

                treeCbi.CheckedMember = nameof( SimpleCbi.IsAlive );

                treeCbi.DataSource = cbis.ToArray();

It's interesting that at least when it's an array, something happens; nothing happens for a list.

[Vijayalakshmi Roopkumar]

Hi Gyorgy 

 

Thank you for contacting Syncfusion Support. 

 

We have checked that the reported behaviour that Items are not populated properly in TreeviewAdv when it is bounded to list type of Items in our sample, and we could find that no items is visible and bounded with ArrayType too. Please find the code and sample below: 

 

Code:[C#] 

 

 

treeViewAdv1.DataRelations.Clear(); 

treeViewAdv1.DataMember = nameof(SimpleCbi.ContinentID); 

treeViewAdv1.DataRelations.Clear(); 

treeViewAdv1.DisplayMember = nameof(SimpleCbi.Name); 

treeViewAdv1.ParentMember = nameof(SimpleCbi.ContinentID); 

treeViewAdv1.ChildMember = nameof(SimpleCbi.CountryID); 

treeViewAdv1.ValueMember = nameof(SimpleCbi.Capital); 

treeViewAdv1.CheckedMember = nameof(SimpleCbi.IsAlive); 

treeViewAdv1.DataSource = dataTable1; 

treeViewAdv2.DataRelations.Clear(); 

treeViewAdv2.DataMember = "Continent"; 

treeViewAdv2.DataRelations.Clear(); 

treeViewAdv2.DisplayMember = nameof(SimpleCbi.Name); 

treeViewAdv2.ParentMember = nameof(SimpleCbi.ContinentID); 

treeViewAdv2.ChildMember = nameof(SimpleCbi.CountryID); 

treeViewAdv2.ValueMember = nameof(SimpleCbi.Capital); 

treeViewAdv2.CheckedMember = nameof(SimpleCbi.IsAlive); 

treeViewAdv2.DataSource = cbis.ToArray(); 

 

 

 

Screenshot shows one with Bounded with Array type and other with DataTable: 

 

 

 

 

Sample: https://www.syncfusion.com/downloads/support/forum/159186/ze/TreeView_dataBinding47013419.zip 

 

So could you please check the sample and confirm us whether our replication on the reported behaviour is same with yours. If so, we will check further on this behaviour , however it is different could you modify our sample into issue reproducible or shows the sample that working fine with ArrayType , it would be very helpful for us to proceed on it further. 

 

Regards, 

Vijaaylakshmi VR